What do billionaire art collectors and train-obsessed 5-year-olds have in common?

They're both drawn to Chris Burden's "Metropolis II," an epic art installation that looks like a toy racetrack or train set on speed.

When Burden briefly opened his studio in Topanga Canyon a year ago to unveil the work, it was an instant hit with contemporary art collectors. One, Nicolas Berggruen, bought the work and promptly loaned it to LACMA for at least 10 years.

Now it's also getting high marks from the preschool and grade-school set.

The artwork does not officially go on display at LACMA until Jan. 14, but the museum organized a series of unannounced trial runs last week to take it through its final testing, and museum visitors of various ages found their way to the car-fueled spectacle.

Granted, it was hard to actually hear every gasp over the din of the traffic — a loud sound effect that the artist has called a "happy accident." But you could see the excitement, with some kids running, jumping, or dragging their parents closer and others staring, mesmerized, like babies watching TV.

The artwork, four years in the making, features about 1,100 Hot Wheels-sized (but custom-made) cars coursing so quickly through 18 lines of traffic that you can see 100,000 cars passing through the system in an hour. There are also about a dozen trains. It resembles a miniature city, complete with a tangle of freeways and pockets of buildings in various styles — a log cabin here, a glittering Art Deco skyscraper there, an Eiffel Tower lookalike in the distance.

Caterina Roiatti from New York said her son Massimo, 5, spotted the exhibition from the Richard Serra sculpture just across the way. Her son was on the move, running in large circles around the piece. He moved too fast for a writer to talk to him.

"He is obsessed," his mother said. "I don't know how we'll get him out of here."

What was her reaction? "We're architects. I'm not so interested in the cars, but I like some of the buildings," Roiatti said. "They are simplified and abstract in interesting ways."

Entertainment lawyer Erik Hyman, 43, was holding one of his 3-year-old twin daughters on his hip. Her reaction was of the silent sort: She reached out as if to grab a car. "You can't touch it because it's delicate," her father said.

Then Hyman put his own reaction in words: "I am not a sophisticated art person," he said. "But I think this will be a gargantuan hit for the museum. Who wouldn't love it?"

Nearby a group of twentysomething hair stylists, dressed in black shirts and black jeans or leggings, looked mesmerized. Rafael Mercado, Aaron Reid, and Alyssa Elliott said they were students at the Toni and Guy hair academy who just happened to follow the crowds to the gallery.

All had smartphones out to take pictures. "I want this at my house. I want to live with it, or inside it. I don't really have the space for it, maybe I'd put it in the garage," said Mercado, who said it reminded him of how much he loved trains as a kid. "I still have a Thomas the Tank Engine pillow somewhere."

Otherwise, the main point of reference for visitors seemed to be futuristic visions from television or movies. Zachary Feldman, 12, who was visiting L.A. with his family from Portland, Ore., said, "It's like something from the movies because you've never seen so many elevated highways in real life. It kind of reminds you of the Jetsons."

Zachary's cousin Jed Cohen, 55, saw the resemblance to Fritz Lang's classic 1927 movie "Metropolis." "It's updated and sped up, but there is still this vibrating, humming machinery on the bottom," he said. (Burden called the work "Metropolis II" after giving the name Metropolis to a much smaller racetrack he sold to a Japanese museum.) Cohen also made a comparison to Ridley Scott's 1982 movie "Blade Runner" because of the city density.

"Have you seen the movie 'The Fifth Element'?" Mercado asked of his friends, referring to the 1997 Luc Besson movie starring Bruce Willis. "These cars aren't flying but it has that kind of sci-fi thing."

"I feel like this is the future," he added later. "We will see this in China in 10 years."

"Ten years? They're more advanced than we are," said Elliott.

"I mean we'll see this become reality," he replied.

They were both surprised to learn that Burden is the same artist behind the Urban Light installation, the cluster of Art Deco lampposts located on Wilshire Boulevard that has become something of a public face of the museum. And they didn't know about his history as a performance artist who tested his own physical limits in works like "5-Day Locker Piece," in which he lived in a small school locker for that period.

But those performances took place in the early '70s. Since then, he has also made urban planning and modern technology part of his work with sprawling model cities like his 1996 "Pizza City," which one critic described as a fantastic blend of a Swiss mountain village and lower Manhattan.